The present disclosure relates generally to solid-state circuits, and more particularly, to a solid-state circuit protection apparatus.
Many known electrical power and distribution systems include circuit breakers configured to completely interrupt current flowing between two points of the system in response to a circuit fault condition such as, for example, a short-circuit condition. Moreover, electromechanical circuit breakers typically take milliseconds to respond to short-circuit fault conditions. Emerging solid-state circuit breakers, therefore, often utilize semiconductor devices such as insulated-gate bipolar transistors (IGBTs), for example, to completely interrupt the current flowing through the circuit.
Conventional solid state circuit breakers based on transistors typically have low surge current capabilities and cannot sustain internal failures. Moreover, the instantaneous change in current level in response to instantaneously interrupting current flow can cause voltage surges that can degrade and/or damage the semiconductor switches leading to stress-induced switch failures. Transient voltage suppressing components are typically implemented in conventional solid-state circuit breakers to protect the transistors from voltage surges. These transient voltage suppressing components, however, increase the cost and complexity of the overall circuit breaker. The transient voltage suppressing components are also susceptible to stress-induced degradation, thereby resulting in unreliable protection of the semiconductor devices over time.